The present invention relates to a drawing table for use more particularly in industrial drawing and the graphic arts.
In general, a drawing table comprises a drawing board equipped with a drawing set which conventionally consists of scale rules mounted on a dividing head. This drawing set is supported by a means permitting its displacement over part of the board.
Fundamentally there are two types of means permitting the displacement of the dividing head and the rules. According to a first type, the means is a pantograph and according to the second it is a vertical rail supported by a carriage which slides on a rail located in the lower part of the board.
Drawing tables equipped with these known means suffer from several disadvantages.
Firstly, they do not permit the dividing head to be used over an angle of 360.degree. because one or other of the scale rules in disadvantageous manner becomes lodged beneath the pantograph arms or beneath the vertical rail where it is then impossible to perform a drawing stroke.
Moreover, in the case of equipment with a vertical rail, it is very difficult to draw to the left of the rail. As a result, such equipment must be equipped with special means permitting their use by left-handed draughtsmen. It must also be noted that there is a dead area along the left-hand side of the board where the rail is lodged in its extreme position. Therefore the draughtsman cannot use the whole board.
Moreover, and particularly in the case of pantograph equipment, numerous accidents occur, particularly head injuries, as a result of the movement of the arms and the counterweights.
Finally, all these tables require the draughtsman to work in the standing position, which increases fatigue.